A．It will remain popular for a long time.    
B．It does not help explain how early states formed.      
C．It cannot be supported by all the people.
D．It should be applied when analyzing hierarchies.

A．To point out changes in voter's attitudes toward toll and tax increases.
B．To suggest that mistakes were made when the highway system was built.
C．To explain why traffic congestion is not as bad as it used to be.
D．To make a point about the current need for infrastructure repairs.

A．Their concerns are likely to diminish in the future.
B．Their concerns are completely justified.
C．Their concerns suggest that voters need better information.
D．Their concerns have mostly been disregarded by governments.